This invention relates to a facsimile machine constructed to allow interconnection with a communications apparatus like a personal computer via an interface.
A facsimile modulator/demodulator (hereinafter referred to as FAX modem) is commercially available in recent years that can transmit data on a personal computer, external to the facsimile machine, to a remote facsimile machine via a telephone line. Used for connecting the personal computer to the telephone line, the FAX modem adds a capability of facsimile transmission and reception to conventional personal computer communications (hereinafter referred to as PC communications).
Since conventional facsimile machines are constructed to print out received image data on a real-time basis, it has not been possible to choose whether to print out the received data. Provision of a memory for storing outgoing and incoming data gives a facsimile machine a potential of expanding its functions.
As an example, the facsimile machine may be provided with an RS-232C interface and software that can handle AT commands. By connecting a personal computer to the facsimile machine via the RS-232C interface, a PC communications capability is added to the facsimile machine so that it can be utilized as a FAX modem or a printer for the personal computer.
The PC communications capability added to the facsimile machine as discussed above is independent of original functions of the facsimile machine. It is therefore necessary to provide a mode select switch on an operating panel of the facsimile machine, for example, for switching it between facsimile mode for performing the ordinary facsimile functions and communications mode for executing PC communications.
It is assumed that the print function in communications mode would normally be used just temporarily after switching the facsimile machine from facsimile mode to communications mode. Therefore, an operator should confirm that the facsimile machine is not currently used for facsimile transmission or reception and operate the mode select switch for switching from facsimile mode to communications mode when using the facsimile machine for a printing job. Upon completion of the printing job, the operator should again operate the mode select switch for returning the facsimile machine from communications mode back to facsimile mode.
It is to be noted that the personal computer and facsimile machine are placed separately from each other in most cases. This means that the operator needs to operate the mode select switch of the facsimile machine which is separated from the personal computer before and after the printing job. The need for such awkward switching operations could make it difficult to effectively use the printing function of the facsimile machine.
If the operator neglects to return the facsimile machine back to facsimile mode after the printing job, the facsimile machine is left in communications mode and it cannot receive messages transmit from other facsimile machines.
On the other hand, if the facsimile machine is so constructed that it is automatically reset to facsimile mode at the end of each data processing job in communications mode, frequent mode switching would be made even when the operator intends to perform successive jobs in communications mode. Therefore, automatic mode switching could prevent fast and smooth communication processes.
Another problem of the prior art is that the facsimile machine set to communications mode becomes inoperable as a peripheral device of the communications apparatus when the communications apparatus is not properly connected to the facsimile machine or the communications apparatus is powered off.